Distributor mechanism having magnetically responsive ball



July 5, 1966 H. L. VAIL, JR, ET

DISTRIBUTOR MECHANISM HAVING MAGNETICALLY RESPONSIVE BALL Filed July 50,1965 FIG INVENTORS HERMAN LANSING VAIL JR. ALFRED L.W.W|LL|AMS BY M F1 3United States Patent 3 DISTRIBUTGR MECHANISM HAVING MAG- NETICALLYRESPONSIVE BALL Herman Lansing Vail, Jr., and Alfred L. W. Williams,Cleveland, Ohio, assignors to Clevite Corporation, a

corporation of Ohio Filed July 30, 1963, Ser. No. 298,756 9 Claims. (Cl.200-19) This invention relates generally to a high voltage vacuum switchand more particularly to a switch which is magnetically actuated.

The device of this invention is uniquely adapted to be employed inconjunction with a piezoelectric ignition system for internal combustionengines. However, the vacuum switch can be used with equal facility inother applications were exacting standards for switching high voltageare required.

In the prior art it has been customary to use a reed type switch inwhich the reeds are disposed in ani-evacuated housing. The reeds in thisconventional arrangement are arranged in partly overlappingrelationship. It is well known that the reed type vacuum switch hasnumerous disadvantages. For instance, the reeds must exhibitmetallurgical characteristics for establishing a suflicient degree ofresiliency to cause the reeds to be deflected in response to magneticactuation to bring the reeds together. On the other hand, the reeds mustbe constructed of sufliciently stiff material to attain a reasonablyiast reaction upon actuation. The balancing of these requirements isdifiicult. The time element is of critical importance inasmuch as thereeds must move rapidly apart upon removal of the magnetic actuatingforce to collapse the (field of flux so that the electric charge is notdissipated .and for the switching to occur at a rate useful for devicesunder consideration. Timing difiiculties are frequently experienced whenthe reeds are too resilient, or become resilient during operation, anddo not part sufliciently fast enough to avoid dissipation of electricalenergy. This problem of constructing the reeds so as to obtain a fastswitching device is made more diflicult by the erosion of the reed tipsafter substantial use. Thus, it is customary to coat the tips with avery high melting point material, such .as tungsten. This material isrelatively heavy and adds to the mass which must be moved by the magnet.In the prior .art the space between the reeds and the area of overlap isa decisive load factor which must .be taken into consideration indetermining the flux of the magnetic circuit and the force required toclose the reeds.

The present invention avoids many of the shortcomings hereinbeforediscussed. Instead of two reeds, the instant invention utilizes arotating ball which periodically closes the circuit between the inputand output conductor. The advantages are obvious. quirements of thereeds are completely eliminated. The dissipation of electric energy asnormally experienced in reed type devices is substantially absent. Agreater accuracy in switching is obtained since the arc gap of thedevice in accordance with this invention is about onehalf of the reedtype switch, as the instant device uses two gaps instead of a singlegap, and no area of overlap exists so that the likelihood of dissipatingelectric energy is substantially reduced.

It is therefore the primary object of this invention to eliminate and/oravoid the shortcomings of the devices of the prior art .by providing adevice generally as aforesaid.

It is another object of this invention to provide a ball type,magnetically actuated, high voltage vaccum The critical metallurgicalre-' Patented July 5, 1966 switch in which the timing for switching theelectric energy is substantially improved and in which electrical and mechanical juxtaposition of the switching device relative to the input andoutput conductors occurs simultaneously.

It is a further object of this invention to provide a ball type highvoltage vacuum switch adapted to be employed as a switching device for amulti-cylinder internal combustion engine ignition system.

For a better understanding of the present invention, together with otherand further objects thereof, reference is had to the followingdescription taken in connection with the accompanying drawings, and itsscope will be pointed out in the appended claims.

In the drawings:

FIGURE 1 is a cross sectional view taken along line 11 of FIGURE 2 ofthis invention illustrating a high voltage vacuum switch;

FIGURE 2 is a plan view of the device of this invention; and

:FIGURE 3 is a schematic representation of a high voltage vacuum switchin a multi-cylinder internal combustion engine piezoelectric ignitionsystem.

One aspect of this invention resides in the provision of a high voltagevacuum switch, which include-s a housing member of electricallyinsulating material in which the housing has an air evacuated circularcavity defining a passageway tor containing a magnetically responsivemember movable within the passageway. An input and an output conduct-orare suitably secured to the housing and insulated from each other andextraneous leakage,

and project part-way into the air evacuated circular cavity for electriccircuit closing position with the magnetic member. A rotatably disposedmagnetic actuator is arranged in close proximity .to the magnetic memberfor rotating the member within and along the passageway, periodically,between the input and output conductors.

Turning now to the drawing, see FIGURES 1 and 2, there is shown asupport member 10 which may be suitably mounted to an internalcombustion engine (not shown). Protruding centrally through the supportmember 10 is a 'rotatively disposed distributor shaft 12 connectible tothe cam shaft or crankshaft of the engine for rotation in unisontherewith. The distributor shaft 12, composed of magneticallynon-responsive material, carries a permanent magnet 14 hereinafterfurther described.

A partly hollow housing member 16 is formed of a material havingsuitable electrically insulating qualities and low permeability to gas.The housing member 16 has the configuration of a circular disc andincludes a central aperture in which is disposed an annular sleeve 17through which the permanent magnet 14 is extended. The h0using 16 isprovided with an air evacuated circular cavity 18 which defines apassageway. To facilitate the construction, the member 16 is fabricatedin two parts, suitably hot sealed together and fused with sleeve 17, anda small opening in one part is used to evacuate the cavity. The opening(not visible) is hot sealed by the application 'of heat to the area ofthe opening with the result that the vacuum within the cavity 18collapses the opening. The support 10 includes a plurality of flanges 11including a clamp 13 on each flange bearing on the housing to retain andcarry the housing member 16 and to make it possible to turn the member16 to change the relative location between the shaft 12 and housing 16.

A ball 20 having magnetically responsive qualities is rotatably disposedwithin the passageway 18 and in rolling contact with the walls thereof.An input 22 and an output conductor 24 are disposed within the housing16 and both conductors extend through the housing and slightly into thepassageway 18. The conductors are located in the housing in axiallyspaced relationship, i.e., one

underneath the other with the housing 16 serving as insulator, see FIG.1, and are in substantially circumferential juxtaposition with respectto each other, see FIG. 2.

The permanent magnet 14 constitutes a magnetic actuator formoving theball 20. The magnet or actuator 14 includes magnetic core portions 140and two pole pieces 14a and 1412 which are spacedly located on oppositesides of the housing with the ball 20 being attracted by the magnet andtherefore normally interposed between the pole pieces 14:: and 14b. Theactuator rotates in unison with shaft 12 and continuously moves the ball20 along with it.

In operation the rotatable magnetic actuator is effective to establish,periodically, simultaneous mechanical and electrical juxtapositionbetween the ball 20 and the input and output conductors 22 and 24,respectively, by moving the ball 20, within the passageway 18 along thecircular path thereof. Each time such juxtaposition takes effect theelectric circuit between the input and output conductors 22, 24,respectively, is closed.

FIGURES 1 and 2 also illustrate the means for advancing or retarding thecircuit closing position of the conductors relative to the rotatableshaft 12. This may be accomplished by manually shifting the relativelocation of the housing member with respect to the shaft 12. It is alsopossible with the use of conventional equipment to automatically changethe relative location of thetwo components to advance or retard thetiming for closing the electric circuit.

Referring now to FIGURE 3, the housing member 16 is provided with foursets of conductors, each set consisting of an input and an outputconductor 22 and 24, respectively, suitably spaced around the outerperiphery of the housing 16 in the same manner as previously discussed,the input conductor 22 being electrically connected to a voltage source28 and the output conductor to a load or spark gap 30. Upon rotation ofthe shaft 12 and the magnetic actuator 14 electrical juxtaposition witheach set of conductors is established in a continuously repeatingsequence. Inasmuch as the electric circuit is closed upon electricaljuxtaposition of the ball relative to said conductors, only a very smallarc is established and, moreover, since the electrical circuit iscompleted within a vacuum, it is possible to space each set ofconductors rather closely together.

While the instant invention can be used as a switching device per se aswell as in a transistorized ignition system for internal combustionengines, the device is particularly suited for use in conjunction withpiezoelectric ignition systems in which the main voltage is generated bya piezoelectric voltage source, not shown. When so used, it is at timesdesirable to include in the circuit a grounding arrangement to bleed offany residual charge that may still remain in the piezoelectric generatorupon discharge of the energy through the conductor cables. When present,this residual charge is preferably eliminated since it will have theeffect of cancelling out any subsequent electric potential generated bythe piezoelectric device. Therefore, there is shown in FIGURE 3,schematically, a grounding means 26, the magnetic actuator 14 may beutilized for this purpose, to rotate in unison with the shaft 12. Foreach set of conductors there is provided one conductor 27circumferentially spaced between the sets of conductors and connected tothe piezoelectric source of potential 28 and underneath the conductor 27there is disposed a ground conductor 29 connected to ground. Uponrotation of the grounding means 26 the circuit between conductors 27 and29 is closed and any residual charge is bled off. Alternatively, theground conductor 29 may be arranged in very close proximity toconductors 22 and 24. One of the pole pieces 14a and 14b is constructedwith a circumferential width to bridge the circuit between conductors 29and 22 after the circuit between conductors 22 and 24 has been broken.The conductor 27 is then not required. Conversely, the grounding means26 itself can be suitably connected to ground and periodically close thecircuit between itself and conductor 27.

While there have been described what are at present considered to be thepreferred embodiments of this invention, it will be obvious to thoseskilled in the art that various changes and modifications may be madetherein without departing from the invention, and it is aimed,therefore, in the appended claims to cover all such changes andmodifications as fall within the true spirit and scope of the invention.

What we claim is:

1. A high voltage vacuum switch comprising, in combination: asubstantially circular housing member of electrically insulatingmaterial having an air evacuated circular cavity defining a passageway;an input conductor and an output conductor each projecting into saidhousing member and each terminating proximate to said passagewaysubstantially flush with the surface thereof: magnetically responsivemeans movably disposed within said passageway; and a rotatably disposedmagnetic actuator arranged proximate to said magnetically responsivemeans for rotating said means along said passageway to establish,periodically, a closed electric circuit between said conductors.

2. A high voltage vacuum switch according to claim 1, wherein saidconductors are located in said housing axially spaced and radially inparallel and in operable proximity to said passageway to establish,periodically, a simultaneous mechanical and electrical juxtapositionwith said magnetically responsive means when said means is rotated.

3. A high voltage vacuum switch according to claim 1, wherein said meansis a magnetically responsive ball.

4. A high voltage vacuum switch comprising, in combination: asubstantially circular housing member of electrically insulatingmaterial having an air evacuated circular cavity defining a passageway;an input conductor and an output conductor each projecting into saidhousing member, the conductors being located therein axially spaced,radially in parallel, and terminating in operable proximity to saidpassageway substantially flush with the surface thereof; a magneticallyresponsive ball movably disposed within said passageway; and a rotatablemag: netic actuator projecting through said housing concentric with saidcircular cavity, said actuator including two pole pieces spacedlylocated on opposite sides of the housing with the said ball interposedtherebetween, said actuator being effective to establish, periodically,by its action on the ball, a closed electric circuit between saidconductors.

5. A high voltage vacuum switch comprising, in combination: a housingmember of electrically insulating material having an air evacuatedcircular cavity defining a passageway; a plurality of input and acorresponding number of output conductors projecting into said housingmember, said conductors being disposed in sets com: posed of a singleinput and a single output conductor, the conductors of a single setbeing located in the housing axially spaced and radially in parallel,and each set being circumferentially spaced relative to any other set ofconductors; magnetically responsive means movably disposed within saidpassageway; and a rotatably disposed magnetic actuator arrangedproximate to said magneticaL, ly responsive means for rotating saidmeans along said passageway to establish, periodically, electricaljuxtaposition with each set in a continuously repeating sequence so longas said means rotates, to effect a closed electric circuit betweenconductors of a single set.

6. A high voltage vacuum switch according to claim 5 connectible to apiezoelectric source of potential, including grounding means rotatablyarranged in operative relation to said housing; and a plurality ofconductors circumferentially spaced on said housing relative to saidsets of conductors and connectible to said piezoelectric source ofpotential to establish, periodically, electrical 5 juxtaposition withsaid grounding means when said means is rotated.

7. A high voltage vacuum switch according to claim 1 connectible to apiezoelectric source of potential, including grounding means rotatablyarranged in operative relation to said housing; and a third conductorcircumferentially spaced on said housing relative to said input andoutput conductors and connectible to said piezoelectric source ofpotential to establish, periodically, electrical juxtaposition with saidground conductor when said conductor rotates.

8. A high voltage vacuum switch according to claim 7, and a fourthconductor connectible to ground, said grounding means being constructedand arranged to establish, periodically, a closed circuit between saidthird and fourth conductors.

9. A high voltage vacuum switch according to claim 1 connectible to apiezoelectric source of potential, a third conduct/or connected toground and spaced in operative proximity to said input conductor, saidactuator being constructed and arranged to establish, periodically, aclosed circuit between said input and third conductors.

References Cited by the Examiner BERNARD A. GILHEANY, Primary Examiner.

H. M. FLECK, Assistant Examiner.

1. A HIGH VOLTAGE VACUUM SWITCH COMPRISING, IN COMBINATION: ASUBSTANTIALLY CIRCULAR HOUSING MEMBER OF ELECTRICALLY INSULATINGMATERIAL HAVING AN AIR EVACUATED CIRCULAR CAVITY DEFINING A PASSAGEWAY;AN INPUT CONDUCTOR AND AN OUTPUT CONDUCTOR EACH PROJECTING INTO SAIDHOUSING MEMBER AND EACH TERMINATING PROXIMATE TO SAID PASSAGEWAYSUBSTANTIALLY FLUSH WITH THE SURFACE THEREOF: MAGNETICALLY RESPONSIVEMEANS MOVABLY DISPOSED WITHIN SAID PASSAGEWAY; AND A ROTATABLY DISPOSEDMAGNETIC ACTUATOR ARRANGE PROXIMATE TO SAID MAGNETICALLY RESPONSIVEMEANS FOR ROTATING SAID MEANS ALONG SAID PASSAGEWAY TO ESTABLISH,PERIODICALLY, A CLOSED ELECTRIC CIRCUIT BETWEEN SAID CONDUCTORS.